1. Field of the Invention
The present invention relates to a caller ID logging feature for a telephone system for automatically dialing a telephone number of a caller ID record stored in a caller ID log.
2. Description of the Related Art
Telephone systems, including residential, wireless, and business telephone systems, are connected via telephone lines to a Central Office (CO) of the telephone company or service provider to which the owner of the telephone system subscribes. Residential telephones are normally directly connected to a telephone line. Wireless telephones transmit their signals to a wireless receiver that is connected to a telephone line or directly to the CO. Business telephone systems typically comprise a plurality of telephone sets or stations sharing one or more telephone lines, with the plural stations connected to a central processor of the telephone system. The central processor is in turn connected to the one or more telephone lines which connect the central processor to the CO. The processor handles switching of incoming calls to and between the telephone stations, interconnection of phones for accommodating conference calls, storage of voice mail messages for the individual stations, and other functions. Residential phones and wireless phones may also have processors for storing or processing information.
The COs now generally provide caller ID information for incoming calls to telephone systems, which is known as incoming caller line identification (ICLID). The ICLID information generally includes the telephone number of the incoming call, a subscriber name associated with the telephone number, a date and time, and other information about the originating location of the call. This information is displayable on a caller ID display unit located at the receiving station of the business, residential, or wireless telephone system when the incoming call causes the receiving station telephone to ring. A further advantageous capability that is available is the caller ID logging function in which the caller ID information is stored in a memory of the telephone set or system when the incoming call is not answered (or, if answered, to keep a log of a user""s activity). Even more advantageous is the ability to automatically dial or redial the telephone number from the stored ICLID information.
The standard formats for telephone numbering plans are usually hierarchical. For example, for telephones in North America, the standard format is prescribed by the North American Numbering Plan (NANP) as a three digit Numbering Plan Area Code (NPA), followed by the three digit office (CO) code, followed by a four digit intraoffice identifier. This format is followed consistently throughout the NANP area and conforms to international numbering standards. However, dialing procedures, which refer to the use of prefixes such, for example, as 0, 1, 10XXX or suffixes to the NANP numbers, vary throughout the NANP and are often locally determined by state regulatory agencies. Therefore the NANP defines, for each NPA, the procedure that must be used to place the following types of calls:
Home NPA Local Callsxe2x80x94Locals calls within a home area code of the telephone system (e.g., calls to your neighbor);
Home NPA Toll Callsxe2x80x94Toll calls within the home area code (e.g., a call from one end of the area covered by the 914 area code to the other end of the area covered by the 914 area code);
Foreign NPA Local Callsxe2x80x94Local calls to a foreign area code (e.g., in a town with split area codes, calling someone across town in the other area code); and
Foreign NPA Toll Callsxe2x80x94Toll calls to a foreign area code (e.g., calls from New York State to Oregon).
Thus, in some parts of the NANP, toll calls within the caller""s home NPA are dialed on a 7-digit basis, whereas in other areas, these same types of toll calls are dialed using the digit xe2x80x9c1xe2x80x9d as a toll indicator prefix and the full 10 digit number.
The telephone number portion of the ICLID information for NANP phones is delivered in a standard format including the three digit area code, the three digit office code, and the four digit intraoffice identifier. To properly return a call logged by the caller ID log, the number as listed in the ICLID record must be altered in most cases to conform with the calling procedure for the dialing user""s area code and the type of call in the caller ID log.
Prior art telephone systems that include an automatic dialback function supply only two options to the user. The first is to dial the number as received and stored. In many cases, however, the Central Office is unable to complete a call using the exact number stored in the memory, and an attempted call using that number results in a misdialed call or an error message. The second option permits the user to selectively edit the number stored in memory which, however, requires that the user enter xe2x80x9cedit modexe2x80x9d and then make the necessary changes to the stored number before then manually initiating the dialing function. User editing of the number is thus frequently required, a procedure that is cumbersome and does not provide a significant improvement in efficiency over simple manual dialing of the number.
Another prior art type telephone system that includes an automatic dialback function is described in commonly-owned U.S. patent application Ser. No. 09/092,371, the entire contents of which are incorporated herein by reference. In that reference, automated dialing is accomplished by pressing one of a plurality of user actuatable keys that are selectively depressible to automatically dial one or more portions of the stored telephone number as may be required by the local central office to properly address and complete the call. The user may also manually enter an additional prefix and/or select a specific available telephone line on which to route the call before actuating one of the keys for automated dialing of the stored number. This system, however, places the entire burden of choosing the correct format on the user.
A telephone system in accordance with the present invention provides the capability for successfully automatically dialing a telephone number stored in a caller ID log by determining the correct dialing procedure for that call and then dialing the telephone number in accordance with the correct dialing procedure, and for automatically learning the correct dialing procedure for the number to be dialed if a correct dialing procedure can not be determined.
In the inventive procedure, the user selects a caller ID record from a caller ID log with a telephone number to be called back. The user then presses a xe2x80x9cdialxe2x80x9d button, in response to which the user""s telephone system looks up the NPA of the telephone number of the selected caller ID record in a memory that includes NPAs and associated algorithms. After the NPA is found in the memory table, the associated algorithm is used to reformat the telephone number in accordance with a specific dialing procedure and the reformatted number is then dialed. If the call is completed, the system""s current association of that caller ID type and reformatting algorithm are deemed correct. However, sometimes the associated algorithm is incorrect, for example because of changes in the assignments of the NPAs. The assignment of NPAs is constantly being altered or revised to provide relief for those NPAs that are near to exhausting their available central office codes. Relief for those NPAs includes boundary realignment, splitting, and overlaying of NPAs. An incorrect algorithm may thus cause an intercept treatment by the telephone system or a wrong number. If the user receives an intercept treatment such, for example, as an error message or completes a call to a wrong number, the user presses the xe2x80x9cdialxe2x80x9d button again without going on-hook. The second pressing of the xe2x80x9cdialxe2x80x9d button in this manner signals the system to update the association record to another algorithm, terminate the previous failed call attempt, and dial again using the new algorithm. This process is repeated until the call is completed successfully, after which the memory has stored the new correct association of the caller ID type and reformatting algorithm.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims.